The present invention generally relates to temperature control systems for maintaining the temperature of an electronic device at a predetermined temperature such as while the device is being tested.
Testing equipment has been utilized in the electronics industry to test the operation of an electronic device under test (DUT) such as an integrated circuit. Often, the testing equipment will include a thermal head having a temperature controlled surface which is brought into thermal engagement with a top surface of the DUT. The thermal head functions to maintain a predetermined temperature during the testing operation.
With some such testing equipment, the thermal head is configured as an evaporator in a refrigeration system including a compressor and condenser. Refrigerant fluid passes to the thermal head in liquid form, where it is expanded. The resulting temperature drop absorbs thermal energy from the electronic device being tested so as to maintain a predetermined temperature.
At certain times, the thermal head is removed from the remainder of the refrigeration system for maintenance purposes. This causes a loss of refrigerant fluid from the refrigeration system, which must be replaced (or “recharged”) before the refrigeration system will be operational again.
Moreover, testing equipment may be limited in the types of devices that can be tested. For example, different testing machines (each having an appropriately configured thermal head) may be required for each type of electronic device. This can lead to increased costs for both testing equipment and maintenance.
Where the refrigeration system is used in an application other than testing, the maintenance of the electronic equipment may lead removal of components of the refrigeration system, which could result in increased costs and complexity. For example, a separate person skilled in refrigeration maintenance (or significant additional training of the person maintaining the electronic components) and equipped with appropriate refrigeration maintenance tools, such as vacuum pump, refrigerant reclaimation system, refrigerant pressure gauges, etc, would be required. Therefore, there exists a need for improved refrigeration system that overcomes the problems associated with the prior art.